Norman J. Pressman

Sputum cytopathology: use and potential in monitoring the workplace environment by screening for biological effects of exposure

Sputum cytopathologic monitoring detects squamous cell lung cancers at an extremely early stage (x-ray negative). It holds further potential for preventing disease by detecting epithelial alterations which reflect environmental hazards. The addition of sputum cytology screening to screening by chest x-ray film does not significantly reduce mortality from all types of lung cancer, but preliminary analysis of Johns Hopkins Lung Project data suggests that mortality from squamous cell carcinoma is reduced. Quantitative automated cytopathology systems and biochemical/immunological cell markers enhance understanding of these precursors and offer great promise for increasing capacity, accuracy, and usefulness in cytopathology screening of workers. Cytological specimens collected over years of screening workers considered at risk may be important to eventually understanding development and prevention of major occupational diseases.

Automatic Cell Identification and Enrichment in Lung Cancer III. Light Scatter and Two Fluorescence Parameters

Two physical parameters were investigated to automatically recognize cells in sputum from human squamous cell carcinoma of the lung and to separate them for preparation by the Papanicolaou methods, for human interactive identification and for automated high resolution image analysis. The two parameters, 0.5-15.0 degrees forward argon-ion laser light scatter to estimate total cell size and 546 nm Acridine orange fluorescence to approximate total cell DNA content, were measured in a flow-through fluorescence activated cell sorting system. Enrichment for neoplastic cells in three cases of squamous cell carcinoma of the lung averaged 7.8-fold over the original sputum when only green fluorescence was used and 10.5-fold using green fluorescence and forward light scatter. The average enrichment for neoplastic cells was 65.6-fold relative to polymorphonuclear deenrichment.

Centrifugal separation of cells in sputum.

A centrifugation technique was developed and used to separate fixed cells from the sputa of patients with bronchogenic squamous cell carcinoma and ones with no evidence of cancer. This article presents the relative frequencies of occurrence of five cell types (i.e., leukocytes, macrophages, squamous, columnar and atypical/cancer) in specimen fractions separated from a discontinuous aqueous Ficoll density gradient. These differential counts show that individual cell types may be selectively collected. Atypical and cancer cells are found at high-density gradient fractions (p congruent to 1.138-1.155 g/ml) with a 10-fold enrichment over unprocessed samples.